# HTS 3811: Antiknock preparations, oxidation inhibitors, gum inhibitors, viscosity improvers, anti-corrosive preparations and other prepared additives, for mineral oils (including gasoline) or for other liquids used for the same purposes as mineral oils:

https://geopax.app/tariffs/catalog/38/3811

Source: [2026 HTS Revision 21 (October 9, 2026)](https://hts.usitc.gov/search?query=3811). Additional duties by country of origin may apply; estimate a shipment's full duty with the tariff calculator: https://geopax.app/tariffs/calculator

## 3811: Antiknock preparations, oxidation inhibitors, gum inhibitors, viscosity improvers, anti-corrosive preparations and other prepared additives, for mineral oils (including gasoline) or for other liquids used for the same purposes as mineral oils:

| Code | Description | General | Special | Column 2 | Units |
| --- | --- | --- | --- | --- | --- |
| 3811 | Antiknock preparations, oxidation inhibitors, gum inhibitors, viscosity improvers, anti-corrosive preparations and other prepared additives, for mineral oils (including gasoline) or for other liquids used for the same purposes as mineral oils: |  |  |  |  |
|  |   Antiknock preparations: |  |  |  |  |
| 3811.11 |     Based on lead compounds: |  |  |  |  |
| 3811.11.10.00 |       Based on tetraethyl lead or on a mixture of tetraethyl lead and tetramethyl lead | Free |  | 30% | kg |
| 3811.11.50.00 |       Other | Free |  | 25% | kg |
| 3811.19.00.00 |     Other | 6.5% | Free (A+,AU,BH,CL,CO,D,E, IL,JO, KR,MA,OM,P, PA,PE,S,SG) | 3.7¢/kg + 60% | kg |
|  |   Additives for lubricating oils: |  |  |  |  |
| 3811.21.00.00 |     Containing petroleum oils or oils obtained from bituminous minerals | 6.5% | Free (A+,AU,BH,CL,CO,D, E,IL, JO,KR,MA,OM,P, PA,PE,S,SG) | 60% | kg |
| 3811.29.00.00 |     Other | 6.5% | Free (A+,AU,BH,CL,CO,D, E,IL, JO,KR,MA,OM,P, PA,PE,S,SG) | 25% | kg |
| 3811.90.00.00 |   Other | 6.5% | Free (A+,AU,BH,CL,CO,D, E,IL, JO,KR,MA,OM,P, PA,PE,S,SG) | 3.7¢/kg + 60% | kg |